What is antithetical parallelism in Hebrew poetry?

Question: "What is antithetical parallelism in Hebrew poetry?"

Answer:
A major literary device in Hebrew poetry is parallelism. Often, the parallelism is synonymous—the same idea is restated in different words, side by side (see Psalm 40:13). Antithetical parallelism provides an antithesis, or contrast. A verse containing antithetical parallelism will bring together opposing ideas in marked contrast. Instead of saying the same thing twice, it says one thing and then a different thing.

The antithetical parallelism in Ecclesiastes 10:2 is quite apparent:

“The heart of the wise inclines to the right,
but the heart of the fool to the left.”

Two hearts, two directions. The wise man’s heart desires one thing, and the fool’s heart desires something completely different. Their inclinations are antithetical.

Often, but not always, antithetical parallelism is set up with the conjunction but. Here’s another example, from Proverbs 19:16:

“He who obeys instructions guards his life,
but he who is contemptuous of his ways will die.”

Again, we have two ideas in antithesis. One person follows advice and thus lives in safety, whereas another person despises his life and is heading for trouble. In this proverb, we have a couple things that do not seem to be complete opposites—and this is what makes the poetry rich.

“Guards his life” contrasts neatly with “will die” in Proverbs 19:16. It’s a choice between life and death. But, strictly speaking, “obeys instructions” is not the opposite of “is contemptuous of his ways.” The poetry requires us to do a little reading between the lines. We can start by asking the question, how is not obeying instructions equal to being contemptuous of one’s ways? The answer could be something like this: disobedience brings destruction, so willful rebellion is tantamount to despising one’s own life. The proverb is communicating more than meets the eye. The full meaning could be stated this way:

“He who obeys instructions loves his life and will preserve it (because the instructions are healthy),
but he who disobeys instructions is showing contempt for his life, and he will die.”

Proverbs 10:2 contains another example of antithetical parallelism:

“Ill-gotten treasures are of no value,
but righteousness delivers from death.”

Or, to fill out the meaning:
“Ill-gotten treasures lead to death and are of no value,
but righteousness, which refuses to cheat others, leads to life—great value, indeed.”

Sometimes, the Hebrew poets used a combination of parallel styles. Consider the words of Wisdom personified in Proverbs 8:35-36:

“For whoever finds me finds life
and receives favor from the Lord.
But whoever fails to find me harms himself;
all who hate me love death.”

The first two lines exhibit synonymous parallelism: finding “life” equals receiving “favor.” Lines 3 and 4 also present synonymous ideas: “harm” is equated with “death.” However, the two halves of the quatrain are in contrast with each other. (Notice but at the start of the third line.) The first two lines, taken together, describe someone who finds Wisdom. The last two lines describe the fate of one who “hates” Wisdom and therefore fails to find it.

Much of the Bible was originally written in poetic form. Psalms, Proverbs, the Song of Solomon, Ecclesiastes, and Lamentations are almost entirely poetic. Most of the prophets also wrote in poetry, some of them exclusively so. Because poetry is so pervasive in the Hebrew writings, it is beneficial for the student of the Bible to study the structure and forms of parallelism.